How to let people register with an invitation code

Hi,

I am building this webapp (webflow - wized - xano) where people can create an account but they do need to have an invitation code. So we have a registration form with name, company name, email, invitation code, and password. The invitation code needs to match with the email.

I am not sure what would be the best way to set this up. Does anybody have any pointers for me?

Thanks!